Dialogue Act Tagging

Implementing two dialogue act taggers using Conditional Random Field.

Baseline tagger features:

• Speaker change indicator.
• First utterance indicator.
• A feature for each tokens in the utterance.
• A feature for each part-of-speech in the utterance.

Advanced Tagger:

• Length of utterance.
• Bigrams of tokens.
• various features extracted from tokens string: e.g. IS_UPPER to indicate whether the token is in upper case.
• A feature for each token and a feature for each POS, like in the baseline.
• Non-words sounds in the utterance, e.g. <Laughter>
• Non-words sounds in the previous utterance, e.g. <Laughter>
• Speaker change indicator: as in the baseline.
• A feature for each part-of-speech in the previous utterance.
• A Bias feature.

Data set

The Switchboard (SWBD), which is a collection of phone dialogues of volunteers over a predetermine topics, is used. The tags in the corpus are the SWBD-DAMSL dialogue acts. See this for the annotation manual.

Conditional Random Field

A python interface of the CRFsuite is used, see this for installation and documentation.

Credit

hw2_corpus_tool.py is written by Christopher Wienberg, a previous TA for CSCI544 at USC.